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931.
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935.
The use of a new technique, Fourier transform infrared (FTIR) chemical imaging, has been demonstrated for the enhancement of latent fingermarks on a number of surfaces. Images of untreated fingermarks on glass backgrounds with excellent ridge detail were acquired using infrared chemical imaging. High quality fingermarks on glass backgrounds were also developed using ethyl cyanoacrylate (super glue) fuming and subsequent infrared chemical imaging. This new method allows the collection of images from backgrounds that traditionally pose problems for current fingermark detection methods. The background may, for example, be highly colored, have a complex pattern, or possess other pattern or image characteristics that make it difficult to separate fingermark ridges using traditional optical or luminescent visualization. One background that has proven to be a challenging surface for the development of latent fingermarks is the Australian polymer banknote. To demonstrate the power and applicability of infrared chemical imaging, fingermarks fumed with ethyl cyanoacrylate were successfully imaged from Australian polymer banknotes.  相似文献   
936.
Forensic analysis of glass samples was performed in different laboratories within the NITE-CRIME (Natural Isotopes and Trace Elements in Criminalistics and Environmental Forensics) European Network, using a variety of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) systems. The main objective of the interlaboratory tests was to cross-validate the different combinations of laser ablation systems with different ICP-MS instruments. A first study using widely available samples, such as the NIST SRM 610 and NIST SRM 612 reference glasses, led to deviations in the determined concentrations for trace elements amongst the laboratories up to 60%. Extensive discussion among the laboratories and the production of new glass reference standards (FGS 1 and FGS 2) established an improved analytical protocol, which was tested on a well-characterized float glass sample (FG 10-1 from the BKA Wiesbaden collection). Subsequently, interlaboratory tests produced improved results for nearly all elements with a deviation of < 10%, demonstrating that LA-ICP-MS can deliver absolute quantitative measurements on major, minor and trace elements in float glass samples for forensic and other purposes.  相似文献   
937.
Infectious microorganisms are important to multiple communities engaged in biodefense and biosecurity, including the agencies responsible for health, defense, law enforcement, agriculture, and drug and food safety. Many agencies have created lists of high priority infectious microorganisms to prioritize research efforts or to formally control the possession and distribution of specific organisms or toxins. However, the biological classification of infectious microorganisms is often complex and ambiguous, leading to uncertainty and confusion for scientists involved in biosecurity work. To address this problem, we created a database, known as the Microbial Rosetta Stone, which resolves many of these ambiguities and includes links to additional information on the microbes, such as gene sequence data and scientific literature. Here we discuss the efforts to coordinate organism names from pathogen lists from various governmental agencies according to biological relatedness and show the overlap of high-priority organisms from multiple agencies. To our knowledge, this is the first comprehensive coordination of pathogens, synonyms, and correct taxonomic names. The organized tables and visual aids are freely available at http://www.microbialrosettastone.com. This website provides a single location where access to information on a broad range of disease-causing organisms and toxins is available to members of the biosecurity community.  相似文献   
938.
Suicide is second only to accidents as the most common cause of death for children and adolescents age 10 to 19 in Canada. All of the pediatric cases that were referred to the Hamilton Regional Forensic Pathology Unit from 1993 to 2002 were reviewed. For the purpose of this study, pediatric deaths were defined as deaths in the age group of 1 day up to and including 19 years of age. Specific criteria for suicide were applied to each case, independent of the manner of death issued by the coroner. The criteria were 3-fold. First, homicide had to be ruled out by the police investigation and autopsy findings. Second, the method had to be consistent with self-infliction. Finally, there had to be some evidence of suicidal intent. Questionable cases were discussed among the authors, and if reasonable intent could not be established, then the case was excluded. The autopsy and police reports were examined in detail regarding age, sex, location and method of suicide, presence of suicide notes, and any contributing psychologic factors or stressors. Of the 501 pediatric autopsies performed during the 10-year period, 31 (6%) met the criteria of suicide. The majority of cases (87%) were in older adolescents (age 15 to 19), and the male to female ratio was 2.4:1. Psychologic factors were identified in some of the cases, including depressed mood (77%), suicidal ideation (45%), previous suicide attempts (23%), and drug or alcohol problems (19%). Most of the suicides (61%) occurred in the victim's home, and 12 (39%) cases left a suicide note. In 9 cases (29%), alcohol or street drugs were detected postmortem, though in 8 cases toxicology was not performed. Hanging (48%) was the most common method of suicide, followed by firearms (13%), poisoning (10%), drowning (10%), and blunt force vehicular trauma (10%). Almost 60% of the male suicides were by hanging. No specific trend was identified in the 9 female suicides. These results were compared with similar studies within Canada and other countries. Overall, the method of suicide is dictated by what is convenient and readily available, though the acceptance of various suicide methods can change over time. Suicide prevention efforts should be tailored to address local trends.  相似文献   
939.
The predictive accuracy of the Psychopathy Checklist-Revised, Level of Service Inventory-Revised, Violence Risk Appraisal Guide, and the General Statistical Information on Recidivism were compared to four instruments randomly generated from the total pool of original items. None of the four original instruments better predicted post-release failure than the four randomly generated instruments. These results suggest two conclusions: (a) the instruments are only measuring criminal risk, and (b) no single instrument has captured sufficient risk assessment theory to result in better prediction than randomly derived instruments measuring criminal risk. A two-stage factor analysis was completed on 1614 cases. This analysis of the risk items indicated a 4-factor solution and all 4 factors were equal to the original instruments in predicting post-release failure. Thus, the original instruments did not improve prediction over randomly structured scales, nor did the restructuring of items improve risk assessment, suggesting substantial deficiencies in the conceptualization of risk assessment and instrumentation. We argue that developing a risk-based construct, which involves hypothesis testing and an explanation of behavior, is the optimal method to advance risk assessment within the criminal justice and mental health systems. Such an approach would provide targeted areas for clinical intervention that are salient to risk.  相似文献   
940.
The growing need for organ and tissue transplants has led a number of states to enforce a policy that views a donor's declared intent to be an organ donor as legally binding. This allows health officials to harvest organs without the permission of the next of kin. Legally binding consent is controversial because of concerns that it may anger family members, lead to negative publicity, and discourage potential donors. We use interviews and a pooled time-series data set of cadaveric donation rates in U.S. states to evaluate the effectiveness of this policy. Our research indicates that enforcement of legally binding consent has marginally increased cadaveric donations while not significantly affecting donor registration. We also find evidence that the effect of the policy might be greater if it were more fully implemented and coordinated with efforts to improve public acceptance and awareness.  相似文献   
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